<!DOCTYPE html>
<html lang="en">
  <head>
    <meta charset="UTF-8" />
    <meta http-equiv="X-UA-Compatible" content="IE=edge" />
    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
    <title>Document</title>
    <style>
      html,
      body {
        width: 100%;
        height: 100%;
        display: flex;
        justify-content: center;
        align-items: center;
      }

      button {
        position: relative;
        outline: none;
        border: none;
        cursor: pointer;
        font-size: 24px;
        font-weight: bold;
        color: #fff;
        width: 300px;
        height: 100px;
        border-radius: 50px;
        text-transform: uppercase;
        background: linear-gradient(90deg, #ffc312, #c4e538, #12cbc4, #ffc312);
        background-size: 400%;
      }

      button:hover {
        animation: move 6s linear infinite;
      }

      button::after {
        content: "";
        position: absolute;
        top: -10px;
        left: -10px;
        bottom: -10px;
        right: -10px;
        z-index: -1;
        background: linear-gradient(90deg, #ffc312, #c4e538, #12cbc4, #ffc312);
        background-size: 400%;
        border-radius: 60px;
        opacity: 0;
        transition: 0.5s;
      }

      button:hover::after {
        filter: blur(18px);
        opacity: 1;
        animation: move 6s linear infinite;
      }

      @keyframes move {
        0% {
          background-position: 0%;
        }
        100% {
          background-position: 400%;
        }
      }
    </style>
  </head>
  <body>
    <button>mstliao</button>
  </body>
</html>
